Rob, I wasn't intending sarcasm, I was just stating it as I see it. You or I don't know what a lot or the majority of photographers or Lightroom users do or want period. Ny the way the site is not designed as a personal blog which in my eyes is the way you come across as treating it.

In my original post, I said: "I think a lot of people would appreciate having this". Although, unlike some things, I actually have a pretty good feel for this one through personal experience. Note: I never said "majority". This is the kind of feature that doesn't warrant a majority of users to be worthwhile. A lot of options in the filename template editor are not used by the majority - that hardly makes them bad ideas...

I have frequent ideas and try to describe them thoroughly, and make a case for them. But I don't believe my posts are outside the scope of this site. Unless that changes, I plan to continue posting as I have been.

One real-life example (please ignore this post if you aren't interested in a use case):

My filenaming scheme up until yesterday (import is via plugin that supports folder-number):

{camera-id}_{folder-number}{filename-number}.{ext}

for example:
NIK3_12345.NEF (so far, I have only used least significant digit of folder number). Note: 5-digit "image-number" - after reaching 100,000 photos, another digit of folder-number would need to be used.

Pros: Simple, short, easy to read, unique, yet sufficient information to find the matching photo on my card before reformatting or after undeleting should that become necessary.

Cons: viewing software does not always order them the way I want (details available upon request).

Starting yesterday:

{date}{photog}{time}{camera-id}{filename-number}.ext

for example:
20110635RC130325NB2345.NEF

Pros: all viewing software I use can display in my preferred order (by alphabetizing), even when photographs from multiple cameras and/or photographers. And, does *not* depend on folder number.

Cons: longer, more complicated, harder to read.

Final thoughts:
===========
Many people prefer a scheme that is as "short and sweet" as possible, as long as it suits their needs (I know this from experience). Having folder number prefix the filename number makes for the shortest scheme, assuming user does want to use filename number - some might even say its *sweet*.

PS - If one day all viewing software I use supports my preferred ordering, and adequately supports critical metadata, I may switch back to the previous "simple-as-possible" scheme, relying soley on metadata over filename for those needs. - contingent upon Lightroom supporting the folder-number that is (unless I'm still using an import plugin that supports folder number, of course). Switching filenaming scheme would also require either filename be settable in SDK, or more sophisticated bulk file renaming in Lightroom, although by then, I may have written a database app to do it - based on pioneering work done by Photographe.

Perhaps the folder-number could be made more accessible to the masses if it were handled as an extension to the filename number, for example:

have multiple versions of the in-camera image number:
- 4-digit that rolls over every 10,000 photos (same as the filename number suffix we have now - does not use folder number).
- 5-digit that rolls over every 100,000 photos (uses least signficant digit of folder number).
- 6-digit that rolls over every 1,000,000 photos (uses last two digits of folder number).
- 7-digit that "never" rolls over (includes full 3-digit folder number).